JPWO2005075555A1 - Thermoplastic elastomer composition, molded article, and low hardness sealing material - Google Patents

Abstract

[A] 5 to 60% by mass of an ethylene / α-olefin copolymer having an intrinsic viscosity of 3.5 dl / g or more measured at 135 ° C. in a decalin solvent, [B] 1 to 20% by mass of a polyolefin resin and [C ] [D] Hydrogenated diene system with respect to a total of 100 parts by mass of 30 to 94% by mass of a mineral oil-based softener (however, the total of [A], [B] and [C] is 100% by mass). 0.1 to 50 parts by mass of a polymer, and at least the [A] ethylene / α-olefin copolymer and the [B] polyolefin resin are dynamically heat-treated in the presence of a crosslinking agent. Thermoplastic elastomer composition, or ethylene / α-olefin copolymer having an intrinsic viscosity of 3.5 dl / g or more measured at 135 ° C. in [A1] decalin solvent in the thermoplastic elastomer composition Combined 20-80 And a thermoplastic elastomer composition substituted with an oil-extended rubber composed of 20% to 80% by mass of [C1] mineral oil softener (where the total of [A1] and [C1] is 100% by mass). is there. Excellent moldability, low hardness, flexibility without bleeding out of softeners such as mineral oil, excellent rubber elasticity (rebound resilience, compression set), and recyclability.

Description

  The present invention relates to a thermoplastic elastomer composition, a molded product using the same, and a sealing material having low hardness. More specifically, the present invention relates to excellent molding processability, low hardness, flexibility, and rubber elasticity (rebound resilience, compression). The present invention relates to a thermoplastic elastomer composition and a molded article which are excellent in permanent set) and have no bleed-out of a mineral oil-based softener, and further to a low-hardness sealing material using the thermoplastic elastomer composition.

  Seals used for office equipment, automobiles, building materials, etc. are very soft and are made from vulcanized rubber, vulcanized foam rubber, foamed polyurethane, or thermoplastic elastomer compositions useful as flexible materials. Improvement studies have been attempted (see Patent Documents 1 to 3). The thermoplastic elastomer composition is disclosed in Patent Document 1 and the like. However, the composition of this document is not sufficiently flexible, and when a softener such as mineral oil is further added, the softener is removed from the molded product. There were problems such as bleeding out and reduced rubber elasticity.

In addition, vulcanized rubber, vulcanized foamed rubber, and foamed polyurethane satisfy the properties such as flexibility and sealability, but have a problem that they do not satisfy the recyclability demanded from the viewpoint of resources in recent years.
JP 2002-201313 A JP 2002-251061 A JP 7-234579 A

  The present invention provides a thermoplastic elastomer composition having excellent molding processability, low hardness, flexibility without bleeding out of a softener such as mineral oil, and excellent rubber elasticity (rebound resilience, compression set). An object of the present invention is to provide a molded article and a low-hardness sealing material.

According to the present invention, the following thermoplastic elastomer composition, molded product thereof, and low-hardness sealing material are provided.
(1) [A] 5 to 60% by mass of an ethylene / α-olefin copolymer having an intrinsic viscosity of 3.5 dl / g or more measured in a decalin solvent at 135 ° C.
[B] 1-20% by mass of a polyolefin-based resin and 30-94% by mass of a [C] mineral oil-based softening agent (provided that the total of [A], [B] and [C] is 100% by mass). For a total of 100 parts by mass
[D] 0.1 to 50 parts by mass of a hydrogenated diene polymer,
At least the [A] ethylene / α-olefin copolymer and the [B] polyolefin resin are dynamically heat-treated in the presence of a crosslinking agent,
Thermoplastic elastomer composition.
(2) [X] [A1] 20-80% by mass of an ethylene / α-olefin copolymer having an intrinsic viscosity of 3.5 dl / g or more measured in decalin solvent at 135 ° C. and [C1] mineral oil softener 5 to 60% by mass of an oil-extended rubber comprising 20 to 80% by mass (provided that the total of [A1] and [C1] is 100% by mass),
[B1] 1 to 20% by mass of a polyolefin-based resin and 30 to 94% by mass of [C2] mineral oil-based softener (however, the total of [X], [B1] and [C2] is 100% by mass). For a total of 100 parts by mass
[D1] containing 0.1 to 50 parts by mass of a hydrogenated diene polymer,
At least the [A1] ethylene / α-olefin copolymer and the [B1] polyolefin resin are dynamically heat-treated in the presence of a crosslinking agent,
Thermoplastic elastomer composition.
(3) The hydrogenated diene polymer [D] includes a hydrogenated polymer containing a monomer unit composed of a conjugated diene compound, a monomer unit composed of a conjugated diene compound, and a vinyl aromatic compound. The thermoplastic elastomer composition according to the above (1) or (2), which is at least one selected from a hydrogenated polymer containing a monomer unit.
(4) The thermoplastic elastomer composition according to any one of (1) to (3), wherein the durometer E hardness according to JIS K6253 is 80 or less.
(5) The content of the ethylene monomer unit constituting the ethylene / α-olefin copolymer [A] and [A1] is a monomer unit composed of an ethylene monomer unit and an α-olefin compound. The thermoplastic elastomer composition according to any one of the above (1) to (4), which is 35 to 95 mol% when the total of all the monomer units contained is 100 mol%.
(6) The thermoplastic elastomer composition according to any one of (1) to (5), wherein the mineral oil softeners [C], [C1] and [C2] are paraffinic mineral oils.
(7) The above crosslinking agent is 1,3-bis (t-butylperoxyisopropyl) benzene, 2,5-dimethyl-2,5-di (t-butylperoxy) hexyne-3, 2,5-dimethyl. An organic peroxide selected from -2,5-di (t-butylperoxy) hexane, α, α-bis (t-butylperoxy) diisopropylbenzene, dicumyl peroxide and di-t-butyl peroxide The thermoplastic elastomer composition according to any one of the above (1) to (6).
(8) The thermoplasticity according to any one of (1) to (7), wherein the ethylene / α-olefin copolymer in the thermoplastic elastomer composition has a cyclohexane insoluble content at 23 ° C. of 60% by mass or more. Elastomer composition.
(9). A molded article comprising the thermoplastic elastomer composition according to any one of (1) to (8).
(10) A low hardness sealing material using the thermoplastic elastomer composition according to any one of (1) to (8).
(11) The low hardness sealing material according to (10), wherein the durometer A hardness according to JIS K6253 is 40 or less.
(12) The low-hardness sealing material according to (10) or (11), which is formed in any one shape selected from an O-ring shape, a sheet shape, and a rod shape.
(13) A container having the low-hardness sealing material according to any one of (10) to (12) as a component.
(14) A container formed by injection molding of a composite composed of a seal portion and a housing portion made of the low-hardness seal material according to any one of (10) to (12).
(15) The container according to (14), wherein the casing is made of a thermoplastic resin and / or a thermoplastic elastomer composition and is recyclable.
(16) A toner case comprising the low-hardness sealing material according to any one of (10) to (12) as a component.

  The thermoplastic elastomer composition of the present invention comprises: [A] an ethylene / α-olefin copolymer having an intrinsic viscosity of 3.5 dl / g or more measured at 135 ° C. in a decalin solvent, and [B] a polyolefin. 100 parts by mass in total of 1 to 20% by mass of a resin and 30 to 94% by mass of [C] mineral oil-based softener (however, the sum of [A], [B] and [C] is 100% by mass). In contrast, [D] contains 0.1 to 50 parts by mass of a hydrogenated diene polymer, and at least the [A] ethylene / α-olefin copolymer and the [B] polyolefin resin are crosslinking agents. By being heat-treated dynamically in the presence, it has excellent molding processability by injection molding, extrusion molding, hollow molding, compression molding, vacuum molding, laminate molding, calendar molding, etc., low hardness, mineral oil softener Bleed out It is flexible and has excellent rubber elasticity (rebound resilience, compression set).

  Another thermoplastic elastomer composition of the present invention is an ethylene / α-olefin copolymer 20 to 80 having an intrinsic viscosity of 3.5 dl / g or more measured at 135 ° C. in a [X] [A1] decalin solvent. 5-60 mass% of oil-extended rubber consisting of 20 mass% and [C1] mineral oil-based softener (however, the sum of [A1] and [C1] is 100 mass%), [B1] 100 mass% in total of 1-20 mass% of polyolefin resin and 30-94 mass% of [C2] mineral oil softener (however, the total of [X], [B1] and [C2] is 100 mass%). [D1] 0.1 to 50 parts by mass of a hydrogenated diene polymer, and at least the [A1] ethylene / α-olefin copolymer and the [B1] polyolefin resin are crosslinking agents. Is not heat treated dynamically in the presence of It has excellent molding processability by injection molding, extrusion molding, hollow molding, compression molding, vacuum molding, laminate molding, calendar molding, etc., low hardness, and flexibility without bleeding out of mineral oil softener Yes, excellent rubber elasticity (rebound resilience, compression set).

The hydrogenated diene polymer [D] is a hydrogenated product of a polymer containing a monomer unit comprising a conjugated diene compound, and a monomer comprising a monomer unit comprising a conjugated diene compound and a vinyl aromatic compound. In the case of at least one selected from a hydrogenated product of a polymer containing a body unit, the durometer E hardness defined by JIS K6253 can be 80 or less, and a soft composition can be obtained.
Moreover, when the cyclohexane insoluble content in 23 degreeC of the ethylene-alpha-olefin copolymer in this thermoplastic elastomer composition is 60 mass% or more, it is excellent in rubber elasticity and mechanical strength.

Further, the molded product of the present invention has low hardness, flexibility without bleeding out of the mineral oil softener, and excellent rubber elasticity (rebound resilience, compression set). Furthermore, since the sealing material of the present invention is composed of a thermoplastic elastomer composition, it can be recycled and is extremely resource-saving.
In addition, containers that use this low-hardness sealant as a component part can be integrally molded in a short time by injection molding the seal part and the casing part made of this sealant, reducing workability and recycling A container having excellent properties can be provided.

FIG. 1 is a photograph showing a container with a seal portion comprising the low hardness seal material of the present invention as a component.
FIG. 2 is a photograph showing a state in which the container with the seal part of FIG. 1 is separated into a seal part and a casing part.
FIG. 3 is an explanatory view showing a water leakage drop test.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Seal part, 2 ... Housing | casing part, 10 ... Container, 11 ... Cover, 12 ... Double clip, 13 ... Corrugated paper, 14 ... Packing, 15 ... Water.

Hereinafter, the present invention will be described in detail.
The thermoplastic elastomer composition according to the first aspect of the present invention comprises [A] an ethylene / α-olefin copolymer having an intrinsic viscosity of 3.5 dl / g or more measured at 135 ° C. in a decalin solvent at 5 to 60% by mass. [B] polyolefin resin 1 to 20% by mass and [C] mineral oil softener 30 to 94% by mass (provided that the total of [A], [B] and [C] is 100% by mass). [D] 0.1 to 50 parts by mass of a hydrogenated diene polymer, and at least the [A] ethylene / α-olefin copolymer and the [B] polyolefin resin. Is dynamically heat-treated in the presence of a crosslinking agent.
The thermoplastic elastomer composition of the second aspect of the present invention is an ethylene / α-olefin copolymer having an intrinsic viscosity of 3.5 dl / g or more measured at 135 ° C. in a [X] [A1] decalin solvent. 5 to 60% by mass of an oil-extended rubber composed of 20 to 80% by mass and 20 to 80% by mass of [C1] mineral oil-based softener (however, the sum of [A1] and [C1] is 100% by mass) [B1] 1 to 20% by mass of a polyolefin-based resin and 30 to 94% by mass of [C2] mineral oil-based softener (however, the total of [X], [B1] and [C2] is 100% by mass). [D1] 0.1 to 50 parts by mass of a hydrogenated diene polymer with respect to a total of 100 parts by mass, and at least the [A1] ethylene / α-olefin copolymer and the [B1] polyolefin resin , Heat treatment dynamically in the presence of crosslinking agents It has been made.

Hereinafter, each component will be described more specifically.
1. Ethylene / α-olefin copolymer ([A] and [A1])
This ethylene / α-olefin copolymer (hereinafter also simply referred to as “EAO copolymer”) is composed of an ethylene monomer unit (a1) and an α-olefin having 3 or more carbon atoms excluding ethylene. And a monomer unit (a2).
The constituent amount of the ethylene monomer unit (a1) is preferably 35 to 95 mol%, more preferably 40 to 90 mol, when the total amount of the monomer units constituting the EAO copolymer is 100 mol%. %, Particularly preferably 45 to 85 mol%. If the amount of the ethylene monomer unit (a1) is too large, the resulting thermoplastic elastomer composition tends to have insufficient flexibility, while if too small, the mechanical strength may not be sufficient.

  The α-olefin that forms the monomer unit (a2) is preferably one having 3 or more carbon atoms, and propylene, 1-butene, 2-butene, isobutene, 1-pentene, and 2-methyl. -1-butene, 2-methyl-2-butene, 3-methylbutene, 1-hexene, 4-methyl-1-pentene, 3-methyl-1-pentene, 1-heptene, 1-octene, 1-decene, 1 -Undecene and the like. These can be used alone or in combination of two or more. Of these, those having 3 to 10 carbon atoms are more preferable. By using such an α-olefin, when the EAO copolymer contains other monomer units, other monomers are used. Can be easily copolymerized. Particularly preferred α-olefins are propylene, 1-butene, 1-hexene and 1-octene, with propylene and 1-butene being more preferred.

  The content of the monomer unit (a2) is preferably 5 to 65 mol%, more preferably 10 to 45 mol%, when the total amount of monomer units constituting the EAO copolymer is 100 mol%. Especially preferably, it is 15-40 mol%. If the amount of monomer unit (a2) is too small, the resulting thermoplastic elastomer composition may not exhibit the desired rubber elasticity. On the other hand, if the amount is too large, the durability of the resulting composition may decrease.

The EAO copolymer may be a binary copolymer composed of the monomer units (a1) and (a2), or these monomer units (a1) and (a2); Furthermore, the polymer (ternary copolymer, quaternary copolymer, etc.) comprised from another monomer unit (a3) may be sufficient. Examples of the other monomer units include monomer units composed of non-conjugated diene compounds.
Non-conjugated diene compounds include linear acyclic diene compounds such as 1,4-hexadiene, 1,5-hexadiene, 1,6-hexadiene, 5-methyl-1,4-hexadiene, 3,7-dimethyl- Non-branched chains such as 1,6-octadiene, 5,7-dimethylocta-1,6-diene, 3,7-dimethyl-1,7-octadiene, 7-methylocta-1,6-diene, dihydromyrcene, etc. Cyclic diene compound, tetrahydroindene, methyltetrahydroindene, dicyclopentadiene, bicyclo [2.2.1] -hepta-2,5-diene, 5-methylene-2-norbornene, 5-ethylidene-2-norbornene, 5- Propenyl-2-norbornene, 5-isopropylidene-2-norbornene, 5-cyclohexylidene-2-norbornene, 5- Alicyclic diene compounds such as-2- norbornene. These can be used alone or in combination of two or more. Of these, 1,4-hexadiene, dicyclopentadiene, 5-ethylidene-2-norbornene and the like are preferable.

  When the EAO copolymer containing the monomer unit (a3) is used, the constituent amount of the monomer unit (a3) is 100 mol of the total amount of monomer units constituting the EAO copolymer. %, Preferably 10 mol% or less, more preferably 1 to 8 mol%. If the amount of the monomer unit (a3) is too large, the durability of the resulting composition may be reduced.

  The intrinsic viscosity of the EAO copolymer (measured at 135 ° C. in a decalin solvent) is 3.5 dl / g or more, preferably 3.8 dl / g or more, more preferably 4.0 to 7.0 dl / g. g. When the intrinsic viscosity is less than 3.5 dl / g, the mineral oil-based softening agent may bleed out from the resulting thermoplastic elastomer composition or rubber elasticity may be reduced.

As the EAO-based copolymer, a halogenated copolymer in which a part of hydrogen atoms in a molecule is substituted with a halogen atom such as a chlorine atom or a bromine atom can be used.
In addition, in the presence of these copolymers, vinyl chloride, vinyl acetate, (meth) acrylic acid, (meth) acrylic acid derivatives [methyl (meth) acrylate, glycidyl (meth) acrylate, (meth) acrylamide Etc.], graft polymers obtained by polymerizing unsaturated monomers such as maleic acid, maleic acid derivatives (maleic anhydride, maleimide, dimethyl maleate, etc.) and conjugated diene compounds (butadiene, isoprene, chloroprene, etc.) You can also
The EAO copolymers can be used alone or in combination of two or more.

  The content of the EAO copolymer [A] contained in the thermoplastic elastomer composition of the first aspect of the present invention is such that the EAO copolymer [A], the polyolefin resin [B], and the mineral When the total amount with the oil-based softener [C] is 100% by mass, it is 5 to 60% by mass, preferably 10 to 58% by mass, and more preferably 15 to 55% by mass. If the content of the EAO-based copolymer [A] is too large, the resulting thermoplastic elastomer composition may not have sufficient flexibility, whereas if it is too small, the mineral oil-based softener [C] may be reduced. May bleed out.

  As the ethylene / α-olefin copolymer [A1] constituting the oil-extended rubber [X] for making the thermoplastic elastomer composition of the second aspect of the present invention, those described above can be used as they are. . The proportions of the EAO copolymer [A1] and the mineral oil softener [C1] constituting the oil-extended rubber [X] are 20 to 80% by mass and 20%, respectively, when the total is 100% by mass. -80 mass%, preferably 25-75 mass% and 25-75 mass%, more preferably 30-70 mass% and 30-70 mass%.

  The content of the oil-extended rubber [X] contained in the thermoplastic elastomer composition of the second aspect of the present invention is such that the oil-extended rubber [X], the polyolefin resin [B], and the mineral oil-based softener When the total with [C2] is 100 mass%, it is 5-60 mass%, preferably 10-58 mass%, more preferably 15-55 mass%. If the content of the oil-extended rubber [X] is too large, the resulting thermoplastic elastomer composition may not be sufficiently flexible. On the other hand, if it is too small, the mineral oil softener [C1] and / or [C2] may bleed out.

  The EAO copolymer ([A] or [A1]) is, for example, ethylene, α-olefin in the presence of a catalyst comprising a Ziegler-Natta catalyst, a soluble vanadium compound, and an organoaluminum compound. In addition, the non-conjugated diene can be obtained by a polymerization method by a medium / low pressure method such as a method of polymerizing while supplying hydrogen as a molecular weight regulator as necessary. The polymerization can be carried out by a gas phase method (fluidized bed or stirred bed) or a liquid phase method (slurry method or solution method).

As the soluble vanadium compound, for example, a reaction product of at least one of VOCl ₃ and VCl ₄ and an alcohol is preferably used. As alcohol, methanol, ethanol, n-propanol, isopropanol, n-butanol, sec-butanol, t-butanol, n-hexanol, n-octanol, 2-ethylhexanol, n-decanol, n-dodecanol, etc. should be used. Among these, alcohols having 3 to 8 carbon atoms are preferably used.

  Examples of the organoaluminum compound include triethylaluminum, triisobutylaluminum, tri-n-hexylaluminum, diethylaluminum monochloride, diisobutylaluminum monochloride, ethylaluminum sesquichloride, butylaluminum sesquichloride, ethylaluminum dichloride, butyl. Examples thereof include aluminum dichloride, methylaluminoxane which is a reaction product of trimethylaluminum and water. Of these, ethyl aluminum sesquichloride, butyl aluminum sesquichloride, a mixture of ethyl aluminum sesquichloride and triisobutyl aluminum, and a mixture of triisobutyl aluminum and butyl aluminum sesquichloride are particularly preferably used. Further, hydrocarbons are preferably used as the solvent, and among these, n-pentane, n-hexane, n-heptane, n-octane, isooctane, and cyclohexane are particularly preferably used. These can be used alone or in combination of two or more.

  The non-oil-extended ethylene / α-olefin copolymer [A] and the oil-extended ethylene / α-olefin copolymer, which is an oil-extended rubber [X], include bale, crumb, pellet, powder Any form of body (including crushed bale) may be used. Further, the non-oil-extended ethylene / α-olefin copolymer [A] and the oil-extended ethylene / α-olefin copolymer [X] may be used in combination.

2. Polyolefin resin ([B] and [B1])
As said polyolefin resin, a homopolymer may be sufficient as long as the sum total of the monomer unit which consists of 1 or more types of alpha olefin exceeds 50 mol%, and a copolymer may be sufficient as it. It may be. In the case of a copolymer, it may be a copolymer of α-olefins or a copolymer of an α-olefin and another monomer copolymerizable with the α-olefin. Good. The polyolefin resin can be a crystalline resin and / or an amorphous resin.

When a crystalline polyolefin resin (Ba) is used as the polyolefin resin, the crystallinity is 50% or more, preferably 53% or more, more preferably 55%, in terms of crystallinity by X-ray diffraction. That's it. The crystallinity is closely related to the density. For example, in the case of polypropylene, the density of the α-type crystal (monoclinic form) is 0.936 g / cm ³ , and the smectic type microcrystal (pseudohexagonal form). The density of is 0.886 g / cm ³ , and the density of the amorphous (atactic) component is 0.850 g / cm ³ . In the case of poly-1-butene, the density of the isotactic crystal component is 0.91 g / cm ³ . The density of the amorphous (atactic) component is 0.87 g / cm ³ .
Thus, the density of the crystalline polyolefin resin (B-a) is preferably from 0.89 g / cm ³ or more, more preferably 0.90~0.94g / cm ^3, crystallinity With this range The degree of conversion can be 50% or more. When the crystallinity of the crystalline polyolefin resin (Ba) is less than 50% and the density is less than 0.89 g / cm ³ , the heat resistance, strength, etc. of the resulting thermoplastic elastomer composition Tend to decrease.

The preferable α-olefin that forms the crystalline polyolefin-based resin (Ba) has 2 or more carbon atoms, and more preferably has 2 to 12 carbon atoms. Of these, propylene and 1-butene are preferred.
The content of the monomer unit (b1) composed of an α-olefin constituting the crystalline polyolefin resin (Ba) is such that the monomer unit constituting the crystalline polyolefin resin (Ba) is the same. When the total amount is 100 mol%, it is preferably 80 mol% or more, more preferably 90 to 100 mol%.
When the crystalline polyolefin-based resin (Ba) is a copolymer, the copolymer may be a block copolymer or a random copolymer. However, in order to obtain a block copolymer having the above-mentioned crystallinity, the total amount of the structural units excluding the monomer unit (b1) composed of α-olefin is the monomer unit constituting the block copolymer. When the total amount of is 100 mol%, it is preferably 40 mol% or less, more preferably 20 mol% or less. The block copolymer can be obtained by living polymerization using a Ziegler-Natta catalyst.

In order to obtain a random copolymer having the above-mentioned crystallinity, the total amount of the structural units excluding the monomer unit (b1) composed of α-olefin is the monomer unit constituting the random copolymer. When the total amount of is 100 mol%, it is preferably 15 mol% or less, more preferably 10 mol% or less.
The random copolymer can be obtained, for example, by polymerizing an α-olefin or the like in the presence of a catalyst component containing a Ziegler-Natta catalyst, a soluble vanadium compound, an organoaluminum compound, and a solvent. Examples of the polymerization method include a medium / low pressure method, and can be carried out by a gas phase method (fluidized bed or stirred bed), a liquid phase method (slurry method or solution method) and the like. In the polymerization, a molecular weight regulator such as hydrogen gas may be used as necessary.
As the soluble vanadium compound, it is preferable to use a reaction product of VOCl ₃ and / or VCl ₄ and an alcohol. Examples of the alcohol include methanol, ethanol, n-propanol, isopropanol, n-butanol, sec-butanol, t-butanol, n-hexanol, n-octanol, 2-ethylhexanol, n-decanol, and n-dodecanol. . Among these, C3-C8 alcohol is preferable.

Examples of the organoaluminum compound include triethylaluminum, triisobutylaluminum, tri-n-hexylaluminum, diethylaluminum monochloride, diisobutylaluminum monochloride, ethylaluminum sesquichloride, butylaluminum sesquichloride, ethylaluminum dichloride, butylaluminum dichloride. And methylaluminoxane, which is a reaction product of trimethylaluminum and water. Of these, ethylaluminum sesquichloride, butylaluminum sesquichloride, a mixture of ethylaluminum sesquichloride and triisobutylaluminum, and a mixture of triisobutylaluminum and butylaluminum sesquichloride are preferred.
Further, the solvent is preferably a hydrocarbon, and particularly preferably n-pentane, n-hexane, n-heptane, n-octane, isooctane, and cyclohexane. These can be used alone or in combination of two or more.

The melting point of the crystalline polyolefin resin (Ba), that is, the maximum peak temperature by differential scanning calorimetry is preferably 100 ° C. or higher, more preferably 120 ° C. or higher. When the melting point is less than 100 ° C., sufficient heat resistance and strength tend not to be exhibited.
Further, the melt flow rate (temperature 230 ° C., load 2.16 kg) (hereinafter, simply referred to as “MFR”) of the crystalline polyolefin resin (Ba) is preferably 0.1 to 1,000 g / 10 minutes. More preferably, it is 0.5-500 g / 10min, More preferably, it is 1-100g / 10min. If this MFR is less than 0.1 g / 10 min, the kneadability and extrusion processability of the raw material composition tend to be insufficient. On the other hand, if it exceeds 1,000 g / 10 minutes, the strength of the resulting thermoplastic elastomer composition tends to be lowered.

Accordingly, the crystalline polyolefin resin (Ba) has a crystallinity of 50% or more, a density of 0.89 g / cm ³ or more, an ethylene monomer unit content of 20 mol% or less, and a melting point of Those having a temperature of 100 ° C. or higher and an MFR of 0.1 to 100 g / 10 min are preferable, and it is particularly preferable to use polypropylene and / or a copolymer of propylene and ethylene having a melting point of 140 to 170 ° C. .
The crystalline polyolefin resin (Ba) can be used alone or in combination of two or more.

When the non-crystalline polyolefin resin (Bb) (hereinafter also referred to as “amorphous polyolefin resin (Bb)”) is used as the polyolefin resin, the crystallinity is determined by X-ray diffraction. The degree of crystallinity is less than 50%, preferably 30% or less, more preferably 20% or less. Further, when viewed from the density, the density of the amorphous polyolefin resin (B2) is preferably 0.85 to 0.89 g / cm ³ , more preferably 0.85 to 0.88 g / cm ³ . .

A preferable α-olefin that forms the amorphous polyolefin-based resin (Bb) has 3 or more carbon atoms, and more preferably has 3 to 12 carbon atoms.
The content of the monomer unit (b2) composed of an α-olefin constituting the amorphous polyolefin resin (Bb) is the monomer constituting the amorphous polyolefin resin (Bb). When the total amount of units is 100 mol%, it is preferably 60 mol% or more.

Examples of the amorphous polyolefin-based resin (Bb) include homopolymers such as atactic polypropylene and atactic poly 1-butene, propylene exceeding 50 mol%, and other α-olefins (ethylene, 1-butene). 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene, 1-decene, etc.), more than 50 mol% of 1-butene and other α-olefins (ethylene , Propylene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene, 1-decene, etc.).
Atactic polypropylene and atactic poly-1-butene can be obtained by polymerization using a zirconocene compound-methylaluminoxane catalyst.
The atactic polypropylene can be obtained as a by-product of the polypropylene exemplified as the crystalline polyolefin polymer (Ba).

When the amorphous polyolefin-based resin (Bb) is a copolymer, the copolymer may be a block copolymer or a random copolymer. However, in the case of a block copolymer, the monomer unit (b2) composed of an α-olefin that exceeds 50 mol% needs to be bonded with an atactic structure. This block copolymer can be obtained by living polymerization using a Ziegler-Natta catalyst. The random copolymer can be obtained by the same method as that for the crystalline polyolefin polymer (Ba).
When the amorphous polyolefin resin (Bb) is a copolymer of an α-olefin having 3 or more carbon atoms and ethylene, the amorphous polyolefin resin (Bb) When the total amount of constituting monomer units is 100 mol%, the content of the monomer unit (b2) composed of the α-olefin is preferably 60 to 100 mol%.

  Examples of the amorphous polyolefin resin (Bb) include atactic polypropylene, a copolymer containing propylene monomer units exceeding 50 mol% and ethylene monomer units, and a copolymer of propylene and 1-butene. Polymers are particularly preferred.

The number average molecular weight Mn in terms of polystyrene by GPC of the amorphous polyolefin resin (Bb) is preferably 1,000 to 20,000, more preferably 1,500 to 15,000.
The said amorphous polyolefin resin (Bb) can be used individually by 1 type or in combination of 2 or more types.
As the polyolefin resin, the crystalline polyolefin resin (Ba) and the amorphous polyolefin resin (Bb) may be used alone, or may be used in combination depending on the purpose and application. Also good.

  The content of the polyolefin resin [B] contained in the thermoplastic elastomer composition of the first aspect of the present invention is as follows: EAO copolymer [A], polyolefin resin [B], and mineral oil softening When the sum total with an agent [C] is 100 mass%, it is 1-20 mass%, Preferably it is 3-18 mass%, More preferably, it is 5-15 mass%. If the content of the polyolefin resin [B] is too large, the resulting thermoplastic elastomer composition tends to have insufficient flexibility, whereas if it is too small, kneadability tends to decrease.

  The content of the polyolefin resin [B1] contained in the thermoplastic elastomer composition of the second aspect of the present invention is as follows: oil-extended rubber [X], polyolefin resin [B1], and mineral oil softening When the sum total with an agent [C2] is 100 mass%, it is 1-20 mass%, Preferably it is 3-18 mass%, More preferably, it is 5-15 mass%. If the content of the polyolefin resin [B1] is too large, the resulting thermoplastic elastomer composition tends to have insufficient flexibility, while if too small, the kneadability tends to decrease.

3. Mineral oil softener ([C], [C1] and [C2])
The mineral oil softener is not particularly limited as long as it is conventionally used for rubber products and the like, and examples thereof include paraffinic, naphthenic, and aromatic mineral oils.
Note that the softener for rice bran made of mineral oil-based hydrocarbon is generally a mixture of three of an aromatic ring, a naphthene ring, and a paraffin chain. Paraffinic chain oils with 50% or more of the total number of carbon atoms in the paraffin chain, and naphthenic mineral oils and aromatic rings with 30-45% of the total number of carbon atoms in the naphthenic ring. Those having 30% or more of the total number of carbons are classified as aromatic mineral oils.
These paraffinic, naphthenic and aromatic mineral oils can be used in combination, and each can be used alone or in combination of two or more. Of these, in any of [C], [C1] and [C2], paraffinic mineral oil is preferable, and hydrogenated paraffinic mineral oil is particularly preferable. Examples of the paraffinic mineral oil include “Diana Process Oil PW90” and “Diana Process Oil PW380” manufactured by Idemitsu Kosan Co., Ltd.

The polystyrene equivalent weight average molecular weight Mw by GPC of the mineral oil softener is preferably 300 to 2,000, more preferably 500 to 1,500. The kinematic viscosity at 40 ° C. is preferably 20 to 800 cSt, more preferably 50 to 600 cSt. Furthermore, the pour point is preferably −40 to 0 ° C., more preferably −30 to 0 ° C.
The mineral oil softener can be used in combination with a low molecular weight hydrocarbon such as polybutene or polybutadiene.

  The content of the mineral oil softener [C] contained in the thermoplastic elastomer composition of the first aspect of the present invention is as follows: EAO copolymer [A], polyolefin resin [B], mineral oil When the total with the system softener [C] is 100% by mass, it is 30 to 94% by mass, preferably 32 to 87% by mass, and more preferably 35 to 80% by mass. If the content of the mineral oil softener [C] is too large, the strength of the resulting thermoplastic elastomer composition tends to be insufficient, and the mineral oil softener [C] may bleed out. is there. On the other hand, if the amount is too small, the flexibility of the resulting thermoplastic elastomer composition tends to be insufficient.

  The mineral oil softener [C2] contained in the thermoplastic elastomer composition of the second aspect of the present invention is the same as the mineral oil softener [C1] constituting the oil-extended rubber [X]. There may be different types. The content of the mineral oil softener [C2] is 30 when the total of the oil-extended rubber [X], the polyolefin resin [B], and the mineral oil softener [C2] is 100% by mass. It is -94 mass%, Preferably it is 32-87 mass%, More preferably, it is 35-80 mass%. If the content of the mineral oil softener [C2] is too large, the strength of the resulting thermoplastic elastomer composition tends to be insufficient, and the mineral oil softener [C2] may bleed out. is there. On the other hand, if the amount is too small, the flexibility of the resulting thermoplastic elastomer composition tends to be insufficient.

  The total amount of the mineral oil-based softener contained in the thermoplastic elastomer composition of the second aspect of the present invention is the same as the total amount of the mineral oil-based softener contained in the thermoplastic elastomer composition of the first aspect. There are few compared. This is because in the second embodiment, the oil-extended rubber [X] already contains the mineral oil-based softener [C1].

4). Hydrogenated diene polymer ([D] and [D1])
The hydrogenated diene polymer is not particularly limited as long as it is a hydrogenated diene polymer containing a monomer unit composed of a conjugated diene compound. (I) Only a monomer unit composed of a conjugated diene compound A (co) polymer hydrogenated product comprising (II) a monomer unit comprising a conjugated diene compound and a monomer unit comprising a compound polymerizable with the conjugated diene compound (for example, a vinyl aromatic compound). And hydrogenated products such as polymers to be contained.
The hydrogenated diene polymer may be a single type or a combination of two or more types for (I) and (II). Moreover, the combination of said (I) and said (II) may be sufficient. This hydrogenated diene polymer may or may not be crosslinked in the thermoplastic elastomer composition.

Examples of (I) include hydrogenated butadiene block copolymers.
The above (II) includes (i) a block copolymer containing a polymer block made of a vinyl aromatic compound and a polymer block made of a conjugated diene compound (for example, a hydrogenated styrene / butadiene block copolymer, Hydrogenated styrene / isoprene block copolymer, hydrogenated styrene / butadiene / isoprene block copolymer, etc.), (ii) a polymer block comprising a vinyl aromatic compound, and a random copolymer comprising a conjugated diene compound and a vinyl aromatic compound. A block copolymer comprising a polymer block, (iii) a block copolymer comprising a polymer block comprising a conjugated diene compound, and a copolymer block comprising a conjugated diene compound and a vinyl aromatic compound, (iv) a conjugate Polymer block comprising diene compound, vinyl aromatic compound and conjugated diene compound And (v) a random copolymer block comprising a conjugated diene compound and a vinyl aromatic compound, and a vinyl aromatic Examples thereof include a block copolymer comprising a compound and a conjugated diene compound and a tapered block in which monomer units comprising a vinyl aromatic compound are gradually increased.

Examples of the conjugated diene compound include 1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, 2-methyl-1,3-pentadiene, 1,3-hexadiene, 4, 5-diethyl-1,3-octadiene, 3-butyl-1,3-octadiene, chloroprene and the like can be mentioned. These can be used alone or in combination of two or more. Of these, 1,3-butadiene, isoprene, and 1,3-pentadiene are preferable.
Examples of the vinyl aromatic compound include styrene, tert-butylstyrene, α-methylstyrene, p-methylstyrene, p-ethylstyrene, divinylbenzene, 1,1-diphenylstyrene, vinylnaphthalene, vinylanthracene, N, N. -Diethyl-p-aminoethylstyrene, vinylpyridine and the like. These can be used alone or in combination of two or more. Of these, styrene is preferred.

As the hydrogenated diene polymer, a halogenated hydrogenated diene polymer in which a part of hydrogen atoms in the molecule is substituted with a halogen atom such as a chlorine atom or a bromine atom can be used.
In addition, in the presence of these polymers, vinyl chloride, vinyl acetate, (meth) acrylic acid, derivatives of (meth) acrylic acid [methyl (meth) acrylate, glycidyl (meth) acrylate, (meth) acrylamide, etc. ] Graft polymers obtained by polymerizing unsaturated monomers such as maleic acid, maleic acid derivatives (maleic anhydride, maleimide, dimethyl maleate, etc.) and conjugated diene compounds (butadiene, isoprene, chloroprene, etc.) You can also.

  The hydrogenation rate of the hydrogenated diene polymer is preferably 70% or more, more preferably 90% or more, and still more preferably 95% or more. The “hydrogenation rate” is the number of olefinic unsaturated bonds in the side chain or main chain of the conjugated diene unit constituting the diene polymer before hydrogenation, It is a value indicating the ratio of the number of olefinically unsaturated bonds in the main chain.

  As the hydrogenated diene polymer, an uncrosslinked polymer may be used, or a crosslinked polymer may be used. Moreover, you may use combining these. The crosslinked hydrogenated diene polymer can be obtained by a conventionally known method such as a method described later.

  The hydrogenated diene polymer has a solution viscosity at 30 ° C. of 5 mass% toluene solution, preferably 5 mPa · s or more, more preferably 10 mPa · s or more. This toluene solution viscosity is a surrogate index of molecular weight, and if it is less than 5 mPa · s, the mechanical strength of the resulting thermoplastic elastomer composition tends to decrease.

  The hydrogenated diene polymer is preferably a hydrogenated styrene / butadiene block copolymer or a hydrogenated styrene / butadiene / isoprene block copolymer.

The hydrogenated diene polymer can be easily produced by a known method. For example, the method disclosed in JP-A-2-36244, that is, a conjugated diene compound and a vinyl aromatic compound can be used as a living anion. A pre-hydrogenation polymer is produced by a polymerization method or the like, and then the pre-hydrogenation polymer is hydrogenated in the presence of a catalyst.
In the living anionic polymerization, an initiator such as an organic lithium compound or an organic sodium compound is usually used. Examples of the organic lithium compound include alkyllithiums such as n-butyllithium, sec-butyllithium, and t-butyllithium, which are preferably used. Moreover, as a solvent used at the time of superposition | polymerization, hydrocarbon solvents, such as hexane, heptane, methylcyclopentane, cyclohexane, benzene, toluene, xylene, 2-methylbutene-1, 2-methylbutene-2, are used. The living anionic polymerization method may be a batch method or a continuous method, and the polymerization temperature is usually in the range of 0 to 120 ° C.

  In living anionic polymerization, ether, tertiary amine, alkali metal (sodium, potassium, etc.) alkoxide, phenoxide, sulfonate, etc. are used in combination, and the type, amount used, etc. are appropriately selected. The ratio of the number of conjugated diene units having an olefinically unsaturated bond in the side chain in the hydrogenated block copolymer to the number of all conjugated diene units can be easily controlled.

Furthermore, the molecular weight of the polymer can be increased by adding a polyfunctional coupling agent or cross-linking agent immediately before the end of the living anionic polymerization to cause a coupling reaction or cross-linking.
As coupling agents, divinylbenzene, 1,2,4-trivinylbenzene, epoxidized 1,2-polybutadiene, epoxidized soybean oil, epoxidized linseed oil, benzene-1,2,4-triisocyanate, Shu Diethyl acetate, diethyl malonate, diethyl adipate, dioctyl adipate, dimethyl phthalate, diethyl phthalate, diethyl terephthalate, diethyl carbonate, 1,1,2,2-tetrachloroethane, 1,4-bis (trichloromethyl) Examples include benzene, trichlorosilane, methyltrichlorosilane, butyltrichlorosilane, tetrachlorosilane, (dichloromethyl) trichlorosilane, hexachlorodisilane, tetraethoxysilane, tetrachlorotin, 1,3-dichloro-2-propanone, and the like. Of these, divinylbenzene, epoxidized 1,2-polybutadiene, trichlorosilane, methyltrichlorosilane, and tetrachlorosilane are preferred.
Examples of the crosslinking agent include divinylbenzene, adipic acid diester, epoxidized liquid butadiene, epoxidized soybean oil, epoxidized linseed oil, tolylene diisocyanate, diphenylmethane diisocyanate, 1,2,4-benzene triisocyanate, and the like.

The pre-hydrogenated polymer obtained as described above is reacted, for example, in a hydrocarbon solvent in the presence of a hydrogenation catalyst at a hydrogen pressure of 1 to 100 kg / cm ² and a temperature in the range of −10 to 150 ° C. Thus, a desired hydrogenated diene polymer can be obtained.

  As a hydrogenation catalyst, a metal element selected from periodic table Ib, IVb, Vb, VIb, VIIb, and Group VIII elements such as Ti, V, Co, Ni, Zr, Ru, Rh, Pd, Hf, Re, and Pt. Including compounds are used. Examples of the compound include metallocene compounds containing elements such as Ti, Zr, Hf, Co, Ni, Pd, Pt, Ru, Rh, and Re, metals such as Pd, Ni, Pt, Rh, and Ru, carbon, silica, A supported heterogeneous catalyst supported on a support such as alumina or diatomaceous earth, a homogeneous Ziegler catalyst comprising a combination of an organic salt or an acetylacetone salt of an element such as Ni or Co, and a reducing agent such as organoaluminum, Ru, Examples include organometallic compounds or complexes such as Rh, fullerenes occluded with hydrogen, and carbon nanotubes. These hydrogenation catalysts can be used singly or in combination of two or more. Of these, metallocene compounds containing elements selected from Ti, Zr, Hf, Co and Ni, and elements selected from Ti, Zr and Hf, which can be hydrogenated in a homogeneous system in an inert organic solvent. Metallocene compounds containing are preferred. Further, a hydrogenation catalyst obtained by reacting an inexpensive and industrially useful titanocene compound with alkyl lithium is also preferred.

  After hydrogenation, the hydrogenated diene polymer produced from the reaction solution is simply removed by removing the catalyst residue as necessary, or by adding a phenol-based or amine-based antioxidant. Release. Isolation of the hydrogenated diene polymer is performed, for example, by adding acetone, alcohol or the like to the reaction solution to precipitate, or by pouring the reaction solution into hot water with stirring and then removing the solvent by distillation. be able to.

  The following commercially available products can be used as the hydrogenated diene polymer. For example, “Septon” manufactured by Kuraray (preferred grades for hydrogenated styrene / butadiene / isoprene block copolymers are 4044, 4055, 4077, etc., and hydrogenated styrene / butadiene block copolymers are 8007, 8004. , 8006, etc.) “Tough Tech” manufactured by Asahi Kasei Co., Ltd. (preferred grades are H1052, H1031, H1041, H1051, H1062, H1943, H1913, H1043, H1075, JT-90P, etc.). ), Etc. “Dynalon” manufactured by JSR (preferred grades as hydrogenated styrene / butadiene block copolymers are 8600, 8900, etc.), etc. “Clayton” (hydrogenated styrene / butadiene block manufactured by Kraton Polymers) Preferred as a copolymer Grade, can be used G1650, G1651, a G1652, G1657 and the like.) And the like.

The content of the hydrogenated diene polymer [D] contained in the thermoplastic elastomer composition of the first aspect of the present invention is as follows: EAO copolymer [A], polyolefin resin [B], and mineral oil When the total amount of the softening agents [C] is 100 parts by mass, it is 0.1 to 50 parts by mass, preferably 0.5 to 45 parts by mass, and more preferably 1 to 40 parts by mass. When there is too much content of the said hydrogenated diene polymer [D], the fluidity | liquidity of the thermoplastic elastomer composition obtained may deteriorate. On the other hand, if the amount is too small, the mineral oil softener [C] may bleed out.
In this case, the combination of ethylene / α-olefin copolymer [A], polyolefin resin [B] and mineral oil softener [C] is 100% by mass. Respectively, 5 to 60% by mass, 1 to 20% by mass and 30 to 94% by mass, preferably 10 to 58% by mass, 3 to 18% by mass and 32 to 87% by mass, more preferably 15 to 55% by mass. %, 5-15% by mass and 35-80% by mass.

  The content of the hydrogenated diene polymer [D1] contained in the thermoplastic elastomer composition of the second aspect of the present invention is as follows: oil-extended rubber [X], polyolefin resin [B1], and mineral oil softener When the total of [C2] is 100 parts by mass, it is 0.1 to 50 parts by mass, preferably 0.5 to 45 parts by mass, and more preferably 1 to 40 parts by mass. When there is too much content of the said hydrogenated diene type polymer [D1], the fluidity | liquidity of the thermoplastic elastomer composition obtained may deteriorate. On the other hand, if the amount is too small, the mineral oil softener [C2] may bleed out.

The thermoplastic elastomer composition of the first and second aspects of the present invention contains other polymer components in addition to the ethylene / α-olefin copolymer, the polyolefin resin and the hydrogenated diene polymer. It may be. Other polymer components are not particularly limited as long as they do not hinder the mechanical strength, flexibility, and the like of the obtained thermoplastic elastomer composition.
Examples of such polymer components include ionomer resins, aminoacrylamide polymers, polyethylene maleic anhydride graft polymers, polyisobutylene, ethylene / vinyl chloride copolymers, ethylene / vinyl alcohol copolymers, ethylene / vinyl acetate copolymers. Polymer, polyethylene oxide, ethylene / acrylic acid copolymer, polypropylene maleic anhydride graft polymer, polyisobutylene and its maleic anhydride graft polymer, chlorinated polypropylene, 4-methylpentene-1 resin, polystyrene, ABS resin, ACS Resin, AS resin, AES resin, ASA resin, MBS resin, acrylic resin, methacrylic resin, vinyl chloride resin, vinylidene chloride resin, polyamide resin, polycarbonate, vinyl alcohol resin, vinyl acetal resin, fluorine Resin, polyether resin, polyethylene terephthalate, nitrile rubber and its hydrogenated product, acrylic rubber, silicone rubber, fluorine rubber, butyl rubber, natural rubber, chlorinated polyethylene thermoplastic elastomer, syndiotactic 1,2-polybutadiene, simple blend Olefin-based thermoplastic elastomer, implant-type olefin-based thermoplastic elastomer, polyvinyl chloride-based thermoplastic elastomer, polyurethane-based thermoplastic elastomer, polyester-based thermoplastic elastomer, polyamide-based thermoplastic elastomer, and fluorine-based thermoplastic elastomer. These polymer components can be used singly or in combination of two or more.

5). Additives In addition to the above components, the thermoplastic elastomer composition of the present invention includes an antioxidant, an antistatic agent, a blocking agent, a sealing property improving agent, a lubricant, an anti-aging agent, a thermal stabilizer, a weathering agent, and a metal inertness. Stabilizers, UV absorbers, light stabilizers, copper damage inhibitors, antibacterial and antifungal agents, dispersants, plasticizers, crystal nucleating agents, flame retardants, tackifiers, foaming aids, dyes, Pigments (such as titanium oxide), colorants such as carbon black, metal powders such as ferrite, inorganic fibers such as glass fibers and metal fibers, organic fibers such as carbon fibers and aramid fibers, composite fibers, inorganics such as potassium titanate whiskers Whisker, glass beads, glass balloon, glass flake, asbestos, mica, calcium carbonate, talc, wet silica, dry silica, alumina, alumina silica, calcium silicate, hydrotalcite Fillers such as powders, diatomaceous earth, graphite, pumice, evo powder, cotton flock, cork powder, barium sulfate, fluororesin, polymer beads, and mixtures thereof, polyolefin wax, cellulose powder, rubber powder, wood powder, etc. Various additives such as an agent and a low molecular weight polymer may be contained.

6). Thermoplastic Elastomer Composition The thermoplastic elastomer composition of the present invention is obtained by dynamically heat-treating at least an ethylene / α-olefin copolymer and a polyolefin resin in the presence of a crosslinking agent. That is, a crosslinked ethylene / α-olefin copolymer and a crosslinked polyolefin resin are included. Moreover, when the hydrogenated diene polymer used at the time of manufacture is an uncrosslinked product, it may be crosslinked by dynamic heat treatment. Note that “dynamically heat-treating” refers to both applying a shearing force and heating.

  Although it does not specifically limit as said crosslinking agent, Each of EAO type | system | group copolymer and polyolefin resin is bridge | crosslinked by dynamic heat processing in the temperature more than melting | fusing point of polyolefin resin, or each of EAO type copolymer and polyolefin resin is carried out. Compounds that can crosslink both are preferred.

  Examples of the crosslinking agent include organic peroxides, phenolic crosslinking agents, sulfur, sulfur compounds, p-quinone, p-quinone dioxime derivatives, bismaleimide compounds, epoxy compounds, silane compounds, amino resins, polyol crosslinking agents, Examples include polyamines, triazine compounds, metal soaps, and the like. These can be used alone or in combination of two or more. Of these, organic peroxides and phenol resin crosslinking agents are preferred.

  Examples of the organic peroxide include 1,3-bis (t-butylperoxyisopropyl) benzene, 2,5-dimethyl-2,5-bis (t-butylperoxy) hexyne-3, 2,5-dimethyl- 2,5-bis (t-butylperoxy) hexene-3,2,5-dimethyl-2,5-bis (t-butylperoxy) hexane, 2,2'-bis (t-butylperoxy)- p-isopropylbenzene, dicumyl peroxide, di-t-butyl peroxide, t-butyl peroxide, p-menthane peroxide, 1,1-bis (t-butylperoxy) -3,3,5-trimethyl Cyclohexane, dilauroyl peroxide, diacetyl peroxide, t-butyl peroxybenzoate, 2,4-dichlorobenzoyl peroxide, p-chlorobenzoyl Okishido, benzoyl peroxide, di (t-butylperoxy) perbenzoate, n- butyl-4,4-bis (t-butylperoxy) valerate, t- butyl peroxy isopropyl carbonate. These can be used alone or in combination of two or more. Of these, 1,3-bis (t-butylperoxyisopropyl) benzene, 2,5-dimethyl-2,5-di (t-butylperoxy) hexyne-3, 2,5-dimethyl-2 , 5-di (t-butylperoxy) hexane and α, α-bis (t-butylperoxy) diisopropylbenzene, dicumyl peroxide, di-t-butyl peroxide are preferred.

  Examples of the phenolic crosslinking agent include p-substituted phenolic compounds represented by the following general formula (I), o-substituted phenol / aldehyde condensates, m-substituted phenol / aldehyde condensates, brominated alkylphenols / aldehydes. Examples include condensates. These can be used alone or in combination of two or more. Of these, p-substituted phenol compounds are preferred.

上記一般式（Ｉ）において、Ｘはヒドロキシル基、ハロゲン化アルキル基又はハロゲン原子であり、Ｒは炭素数１〜１５の飽和炭化水素基、ｎは０〜１０の整数である。

In the said general formula (I), X is a hydroxyl group, a halogenated alkyl group, or a halogen atom, R is a C1-C15 saturated hydrocarbon group, n is an integer of 0-10.

  The p-substituted phenol compound can be obtained by a condensation reaction between a p-substituted phenol and an aldehyde (preferably formaldehyde) in the presence of an alkali catalyst.

The amount of the crosslinking agent used is preferably 0.01 to 20 parts by mass, more preferably 0.1 to 0.1 parts by mass with respect to 100 parts by mass of the total amount of polymer components used in the production of the thermoplastic elastomer composition of the present invention. 15 parts by mass, more preferably 1 to 10 parts by mass.
In addition, when using an organic peroxide as said crosslinking agent, Preferably it is 0.05-10 mass parts, More preferably, it is 0.1-5 mass parts. When the amount of the organic peroxide used is too large, the degree of cross-linking becomes excessively high, and the moldability tends to deteriorate or the mechanical properties tend to decrease. On the other hand, if the amount is too small, the degree of crosslinking may be insufficient, and the rubber elasticity and mechanical strength of the resulting thermoplastic elastomer composition may be reduced.
Moreover, when using a phenol type crosslinking agent as said crosslinking agent, Preferably it is 0.2-10 mass parts, More preferably, it is 0.5-5 mass parts. When there is too much usage-amount of this phenol type crosslinking agent, it exists in the tendency for a molding processability to deteriorate. On the other hand, if the amount is too small, the degree of crosslinking may be insufficient, and the rubber elasticity and mechanical strength of the resulting thermoplastic elastomer composition may be reduced.

In addition, the said crosslinking agent can perform a crosslinking reaction gently by using together with a crosslinking adjuvant or a crosslinking accelerator, and can form especially uniform bridge | crosslinking. In particular, when an organic peroxide is used as the crosslinking agent, sulfur, a sulfur compound (powder sulfur, colloidal sulfur, precipitated sulfur, insoluble sulfur, surface-treated sulfur, dipentamethylene thiuram tetrasulfide, etc.), oxime compound (p -Quinone oxime, p, p'-dibenzoylquinone oxime, etc.), polyfunctional monomers (ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tetraethylene glycol di) (Meth) acrylate, polyethylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, diallyl phthalate, tetraallyloxyethane, triallyl cyanurate, N, N′-m-phenylenebismaleimide, N, N ′ -G Lee bismaleimide, maleic anhydride, divinylbenzene, are preferably used di (meth) zinc acrylate and the like) or the like of the crosslinking aid. These can be used alone or in combination of two or more. Of these, p, p′-dibenzoylquinone oxime, N, N′-m-phenylenebismaleimide, and divinylbenzene are preferred.
Of the above-mentioned crosslinking aids, N, N′-m-phenylenebismaleimide can also be used as a crosslinking agent because it has an action as a crosslinking agent.

  When the organic peroxide is used as the crosslinking agent, the amount of crosslinking aid used is preferably 10 parts by mass or less, with respect to 100 parts by mass of the total amount of the polymer components used for producing the thermoplastic elastomer composition. More preferably, it is 0.2-5 mass parts. When the amount of the crosslinking aid used is too large, the degree of crosslinking becomes excessively high, and molding processability tends to be lowered, or mechanical properties tend to be lowered.

  In addition, when a phenolic crosslinking agent is used as the crosslinking agent, metal halides (such as stannous chloride and ferric chloride), organic halides (such as chlorinated polypropylene, butyl bromide rubber, and chloroprene rubber) are used. A crosslinking accelerator can be used in combination to adjust the crosslinking rate. In addition to the crosslinking accelerator, it is more desirable to use a metal oxide such as zinc oxide or a dispersant such as stearic acid.

The thermoplastic elastomer composition of the present invention contains a cross-linked ethylene / α-olefin copolymer, and the content of the cross-linked ethylene / α-olefin copolymer is evaluated by an insoluble content with respect to cyclohexane. be able to. That is, the cyclohexane insoluble content at 23 ° C. of the ethylene / α-olefin copolymer contained in the thermoplastic elastomer composition is preferably 60% by mass or more, more preferably 65% by mass or more, and further preferably 70% by mass. That's it. If the cyclohexane insoluble content is less than 60% by mass, rubber elasticity and mechanical strength may decrease. In addition, the measuring method of the said cyclohexane insoluble content is as follows.
<Method for measuring cyclohexane insoluble matter>
About 200 mg of the thermoplastic elastomer composition is weighed and cut into pieces. Thereafter, the obtained strip is immersed in 100 ml of cyclohexane at 23 ° C. for 48 hours in a sealed container. The cyclohexane solution is then filtered and the residue on the filter paper is dried for 1 hour by a vacuum dryer (105 ° C.). A value obtained by subtracting the mass of the dry residue and the amount of the theoretical mineral oil-based softener in the thermoplastic elastomer composition from the mass of the thermoplastic elastomer composition before dipping ([A], [A1] Crosslinked ethylene / α-olefin copolymer) is defined as “corrected final mass (p)”.
On the other hand, from the mass of the thermoplastic elastomer composition before immersion, the mass of the ethylene / α-olefin copolymer (total amount of [A] and [A1]) is determined, and “corrected initial mass (q)” is obtained. And
Here, the cyclohexane insoluble content is (insoluble content in the EAO copolymer / total amount of the EAO copolymer), and is obtained by the following formula.
Cyclohexane insoluble matter [mass%] = [{corrected final mass (p)} ÷ {corrected initial mass (q)}] × 100

  The durometer E hardness (according to JIS K6253) of the thermoplastic elastomer composition of the present invention is preferably 80 or less, more preferably 75 or less, still more preferably 70 or less.

7). Method for Producing Thermoplastic Elastomer Composition The method for producing the thermoplastic elastomer composition of the present invention includes an ethylene / α-olefin copolymer and a polyolefin resin that are dynamically heat-treated in the presence of a crosslinking agent. If it is a method, it will not specifically limit.
As a general method, a raw material composition containing an ethylene / α-olefin copolymer, a polyolefin resin, a mineral oil softener, a hydrogenated diene polymer, and a crosslinking agent is prepared. Dynamic heat treatment is performed.
As another method, a raw material composition containing (i) an ethylene / α-olefin copolymer (or oil-extended rubber), a polyolefin resin and a crosslinking agent is prepared, and dynamic heat treatment is performed on the raw material composition. And (ii) a raw material composition comprising an ethylene / α-olefin copolymer (or oil-extended rubber), a polyolefin resin, a hydrogenated diene polymer, and a crosslinking agent. After preparing and performing the dynamic heat treatment of this raw material composition, a method of adding other raw material components can be used.

  The ethylene / α-olefin copolymer, polyolefin resin, and hydrogenated diene polymer used in preparing the raw material composition may be used as they are, or as compositions containing the same or different additives, respectively. It may be used. The shape when using the ethylene / α-olefin copolymer may be any of bale, crumb, pellet, and powder (including crushed product of bale or crumb). -You may use combining an alpha-olefin type copolymer.

  The ethylene / α-olefin copolymer [A], the polyolefin resin [B], and the mineral oil softener [A] in all the raw material components (I) used to make the thermoplastic elastomer composition of the first embodiment The combination of the contents of C] is 5 to 60% by mass, 1 to 20% by mass, and 30 to 94% by mass, preferably 10 to 58% by mass, when the total of these is 100% by mass. It is 3-18 mass% and 32-87 mass%, More preferably, it is 15-55 mass%, 5-15 mass%, and 35-80 mass%.

In order to obtain the thermoplastic elastomer composition of the second aspect, an oil-extended rubber [X] comprising an ethylene / α-olefin copolymer [A1] and a mineral oil softener [C1] is prepared in advance. The oil-extended rubber [X] is used together with other raw material components such as a crosslinking agent.
The oil-extended rubber [X], the polyolefin resin [B1], and the mineral oil softener [C2] in all the raw material components (II) used to make the thermoplastic elastomer composition of the first aspect The combination of the amounts is 5 to 60% by mass, 1 to 20% by mass, and 30 to 94% by mass, preferably 10 to 58% by mass and 3 to 18% by mass, when these totals are 100% by mass. % And 32-87 mass%, more preferably 15-55 mass%, 5-15 mass% and 35-80 mass%.

An apparatus used for “dynamically heat-treating” when producing the thermoplastic elastomer composition includes a melt-kneading apparatus. The treatment by the melt kneader may be a continuous type or a batch type.
Examples of the melt kneader include an open type mixing roll, a non-open type Banbury mixer, a single screw extruder, a twin screw extruder, a continuous kneader, and a pressure kneader. Among these, it is preferable to use a continuous melt kneader such as a single screw extruder, a twin screw extruder, or a continuous kneader from the viewpoint of economy, processing efficiency, and the like. Two or more of the same or different apparatuses may be used in combination as the continuous melt-kneading apparatus.

When using the said twin-screw extruder, it is preferable that L / D (ratio of the screw effective length L and the outer diameter D) is 30 or more, More preferably, it is 36-60. Moreover, as this twin-screw extruder, for example, any twin-screw extruder such as one in which two screws mesh or not mesh can be used, but the rotation direction of the two screws is the same direction. What engages with a screw is more preferable.
Examples of such a twin screw extruder include “PCM” manufactured by Ikegai Co., Ltd., “KTX” manufactured by Kobe Steel Co., Ltd., “TEX” manufactured by Nippon Steel Co., Ltd., “TEM” manufactured by Toshiba Machine Co., Ltd., “ZSK” manufactured by Warner Co. Is mentioned.

Moreover, when using the said continuous kneader, it is preferable that L / D (ratio of the screw effective length L and the outer diameter D) is 5 or more, More preferably, it is L / D10.
Examples of such a continuous kneader include “Mixtron KTX / LCM / NCM” manufactured by Kobe Steel, “CIM / CMP” manufactured by Nippon Steel.

The treatment temperature during the dynamic heat treatment is usually 120 to 350 ° C, preferably 150 to 290 ° C. The treatment time is usually 20 seconds to 320 minutes, preferably 30 seconds to 25 minutes.
The shearing force applied to the mixture is 10 to 20,000 / sec, preferably 100 to 10,000 / sec in terms of shear rate.

  The thermoplastic elastomer composition obtained as described above has low hardness, particularly duro E and duro A, is flexible, and is excellent in rubber elasticity. Therefore, the above-described excellent properties can be utilized even when a molded product comprising only this thermoplastic elastomer composition is used according to the purpose and application. Examples of the method for producing a molded article comprising the thermoplastic elastomer composition of the present invention include an extrusion molding method, a calender molding method, a solvent casting method, an injection molding method, a vacuum molding method, a powder slush molding method, and a heating press method. Can be mentioned.

8). Molded Article The molded article of the present invention is characterized by comprising the thermoplastic elastomer composition.
The molded product of the present invention can be a product that is compounded with a component made of another material by lamination, bonding, or the like.
Examples of other materials include rubber, resin, thermoplastic elastomer composition other than the present invention, metal (alloy), glass, cloth, wood, and the like.

As rubber | gum and resin, what was illustrated as another polymer component which can be mix | blended with the thermoplastic elastomer composition of this invention can be used.
As metals (alloys), stainless steel, aluminum, iron, copper, nickel, zinc, lead, tin, nickel / zinc alloys, iron / zinc alloys, lead / tin alloys used in automobiles, ships, home appliances, etc. Etc.

9. Sealing material comprising thermoplastic elastomer composition:
Among the thermoplastic elastomer compositions of the present invention, those having a duro A hardness of 40 or less, preferably 35 or less, more preferably 30 or less, particularly preferably 22 or less in accordance with JIS K6253 are preferably used as a sealing material. . The thermoplastic elastomer composition has a compression set (measurement condition: 70 ° C., 22 hours) in accordance with JIS K6262, preferably 40% or less, more preferably 38% or less, and further preferably 35% or less. small. The sealing material using the thermoplastic elastomer composition having such characteristics is extremely excellent in sealing properties, and is composed of the thermoplastic elastomer composition without causing the mineral oil softener to bleed out. Therefore, recycling is easy and easy, and resource saving is extremely excellent.

Examples of the method for producing the sealing material comprising the thermoplastic elastomer composition of the present invention include an extrusion molding method, a calender molding method, a solvent casting method, an injection molding method, a vacuum molding method, a powder slush molding method, and a heating press method. Can be used.
Although it does not specifically limit as a shape of the sealing material obtained, For example, O-ring shape, sheet | seat shape, or rod shape etc. are mentioned. Further, the sealing material can be used as a stopper.

The seal material of the present invention is formed in a seal portion, and is combined with components such as a casing portion made of other materials by lamination, bonding, etc., for example, a toner case for a copying machine or a printer. Product such as a simple container. Here, examples of the other material include rubber, resin, thermoplastic elastomer composition other than the present invention, metal (alloy), glass, cloth, and wood.
In the case of a product such as a container, the casing may be made of various materials as described above, but is preferably made of a recyclable material. Among them, a case in which the casing portion is made of a thermoplastic resin and / or a thermoplastic elastomer composition is preferable because it is recyclable and easy.

  Examples of the thermoplastic resin, the thermoplastic elastomer, and the thermoplastic elastomer composition for the recyclable casing are exemplified as other polymer components in the description of the raw material composition used to form the thermoplastic elastomer composition. Of these, those having thermoplasticity are preferably used. For example, ionomer resin, aminoacrylamide polymer, polyethylene and its maleic anhydride graft polymer, polyisobutylene, ethylene / vinyl chloride copolymer, ethylene / vinyl alcohol copolymer, ethylene / vinyl acetate copolymer, polyethylene oxide, Ethylene / acrylic acid copolymer, polypropylene and its maleic anhydride graft polymer, polyisobutylene and its maleic anhydride graft polymer, chlorinated polypropylene, 4-methylpentene-1 resin, polystyrene, ABS resin, ACS resin, AS Resin, AES resin, ASA resin, MBS resin, acrylic resin, methacrylic resin, vinyl chloride resin, vinylidene chloride resin, polyamide resin, polycarbonate, vinyl alcohol resin, vinyl acetal resin, fluorine resin Polyether resin, polyethylene terephthalate, chlorinated polyethylene thermoplastic elastomer, syndiotactic 1,2-polybutadiene, simple blend type olefin thermoplastic elastomer, implant type olefin thermoplastic elastomer, dynamically cross-linked olefin thermoplastic elastomer , Polyvinyl chloride thermoplastic elastomer, polyurethane thermoplastic elastomer, polyester thermoplastic elastomer, polyamide thermoplastic elastomer, and fluorine thermoplastic elastomer. These polymer components can be used singly or in combination of two or more.

In addition, if an olefin-based material that is compatible with the sealing material is selected as the material on the housing side, a container in which the housing portion and the sealing portion are heat-sealed can be obtained. On the other hand, if a material that is incompatible with the sealing material (for example, a thermoplastic resin containing a functional group) is selected as the material for the housing, the sealing portion and the housing can be combined without fusing. Can do.
More specifically, examples of the material on the housing side compatible with the sealing material include polypropylene and polyethylene, and examples of the material on the housing side compatible with the sealing material include ABS resin, polycarbonate, and polystyrene. .
As the container of the present invention, a metal (alloy), glass, cloth, wood, or the like, which is a material other than a thermoplastic resin or a thermoplastic elastomer composition, can be used. For example, as the metal (alloy), stainless steel, aluminum , Iron, copper, nickel, zinc, lead, tin, nickel / zinc alloys, iron / zinc alloys, lead / tin alloys used in automobiles, ships, home appliances, and the like.

  The sealing material of the present invention can be formed in a container (a casing part to which the sealing part is attached) by forming this in a sealing part, and preferably by combining with a casing part by injection molding. . In the container, the sealing portion made of the sealing material of the present invention can exhibit extremely excellent sealing performance when storing contents such as powder and liquid such as toner.

  As a compounding method by injection molding, two or more kinds of resins such as core back method, die slide method, rotary method, etc. are sequentially injected and filled into the mold from different injection cylinders, dissimilar materials Or the molding method which makes the molded article of a different color material is mentioned. Multi-layered or multicolor molded products can be obtained by multiple injections.

  In the rotary method, the material of the first color (first material) is injection molded from the first cylinder, the mold is opened once, and the mold turntable is rotated 180 ° with the primary molded product attached to the core side. The mold is closed, the second color (second material) is injection molded from the second cylinder, the mold is opened again, and the molded product is taken out from the mold to produce a combined injection molded product. Is the method.

  The core back method consists of primary molding and secondary molding. At the time of primary molding, a part of the cavities is sealed with a moving core, and molten resin is injected and filled into the vacant cavities to form a primary semi-molded product. In this method, the movable core is retracted during secondary molding, and a molten resin is injected into the retracted space to obtain a molded product integrated with the primary semi-molded product.

As a manufacturing method of a container using the sealing material of the present invention, a die slide method [DSI (Die Slide Injection)] can be mentioned as a preferable molding method among injection molding. A brief description of the DSI method is as follows.
First, with the mold closed, a primary molded product (hollow product halves) is molded by primary injection, and the mold is opened while the primary molded product remains in the cavity. The mold has a structure that can be moved by a die slide mechanism provided in the injection molding machine. With this mechanism, the mold is moved to a position where the primary molded products face each other. The mold is closed again, and the resin is secondarily injected in a bee-wound shape and integrated so as to wrap around the joint where the primary molded product is abutted. The hollow article molding method is described in, for example, plastic swage “Development of Hollow Injection Molding Technology by DSI” (Aug. 2002), p 74-84 and Japanese Patent Application Laid-Open No. 62-87315.

  Hereinafter, the present invention will be specifically described with reference to examples. In addition, this invention is not restrict | limited at all by these Examples. Further, “%” and “part” in the examples are based on mass unless otherwise specified.

[Example 1]
1. Manufacture of thermoplastic elastomer composition Table below shows ethylene / α-olefin copolymer and mineral oil softener (hydrogenated paraffinic mineral oil manufactured by Idemitsu Kosan Co., Ltd., trade name “Diana Process Oil PW380”). An oil-extended rubber (I) containing at a ratio shown in 1 was prepared. Thereafter, the oil-extended rubber (I), the polyolefin resin shown below, the mineral oil-based softener, the hydrogenated diene polymer, and various additives excluding the crosslinking agent and the crosslinking aid are listed in Table 2. The raw material composition was obtained by mixing at a blending ratio of This raw material composition was put into a pressure type kneader (capacity 10 liters, manufactured by Moriyama Co., Ltd.) preheated to 150 ° C., and 40 rpm (shear rate 200 / sec) until the polyolefin resin melted and each component was uniformly dispersed. ) For 15 minutes, and then the obtained kneaded material in a molten state was pelletized by a feeder ruder (manufactured by Moriyama Co., Ltd.).
Next, the pellets, the crosslinking agent and the crosslinking aid were charged into a Henschel mixer at the ratio shown in Table 2, and mixed for 30 seconds. Then, using a twin screw extruder (same direction fully meshed screw, ratio L / D of screw flight part length L to screw diameter D = 33.5, manufactured by Ikegai Co., Ltd., model PCM45), retained at 200 ° C. Extrusion was performed while performing dynamic heat treatment at a processing time of 1 minute 30 seconds, 300 rpm, and a shear rate of 400 / sec to obtain a pellet-shaped thermoplastic elastomer composition.

(1) Ethylene / α-olefin copolymer (I) Ethylene / propylene / 5-ethylidene-2-norbornene terpolymer An ethylene monomer unit amount is 66 mol%, 5-ethylidene-2-norbornene monomer The monomer unit amount is 4.5 mol%, and the intrinsic viscosity measured at 135 ° C. in a decalin solvent is 5.5 dl / g.
(II) Ethylene / propylene / 5-ethylidene-2-norbornene terpolymer An ethylene monomer unit amount is 66 mol% and a 5-ethylidene-2-norbornene monomer unit amount is 4.5 mol%. The intrinsic viscosity measured at 135 ° C. in a decalin solvent is 2.7 dl / g.

(2) Polyolefin resin (I) Crystalline polypropylene Product name “Novatech FL25R” (density: 0.90 g / cm ³ , MFR (temperature 230 ° C., load 2.16 kg); 23 g / 10 min) manufactured by Nippon Polychem Co., Ltd. Was used.
(II) Propylene / 1-butene amorphous copolymer, manufactured by Ube Lexen, trade name “UBETAC APAO UT 2780” (propylene monomer unit amount: 71 mol%, melt viscosity: 8,000 cPs, density; 87 g / cm ³ , crystallinity by X-ray diffraction; 0%, number average molecular weight Mn in terms of polystyrene by GPC; 6,500).

(3) Hydrogenated diene polymer (I) Styrene / butadiene / isoprene hydrogenated diene polymer Product name “Septon 4077” manufactured by Kuraray Co., Ltd. (styrene monomer unit amount: 30 mol%, specific gravity: 0.91 Hydrogenation rate: 98%, toluene solution viscosity (30 ° C., concentration 5 mass%); 300 mPa · s, melt flow rate (230 ° C., 21.2 N) does not flow and cannot be measured).
(II) Styrene-butadiene hydrogenated diene polymer, trade name “Septon 8006” manufactured by Kuraray Co., Ltd. (styrene monomer unit amount: 30 mol%, specific gravity: 0.91, hydrogenation rate: 98%, toluene solution viscosity (30 ° C., concentration 5 mass%); 42 mPa · s, melt flow rate (230 ° C., 21.2 N) does not flow and cannot be measured).
(III) Styrene-butadiene hydrogenated diene polymer, trade name “G1651” manufactured by Kraton Polymers (styrene monomer unit amount: 33 mol%, specific gravity: 0.91, hydrogenation rate: 99%, toluene solution viscosity (30 ° C., concentration 5 mass%); 50 mPa · s, melt flow rate (230 ° C., 21.2 N) does not flow and cannot be measured).

(4) Additive (i) Cross-linking agent The trade name “Perhexa 25B-40” (5-dimethyl-2,5-di (t-butylperoxy) hexane) manufactured by NOF Corporation was used.
(Ii) Crosslinking aid Divinylbenzene (purity: 96%) manufactured by Nippon Steel Chemical Co., Ltd. was used.
(Iii) Anti-aging agent The brand name "Irganox 1010" (tetrakis [methylene 3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] methane) manufactured by Ciba Specialty Chemicals was used.

2. Evaluation of Thermoplastic Elastomer Composition The pellets of the thermoplastic elastomer composition obtained above were processed by an injection molding machine (model “N-100” manufactured by Nippon Steel Works), and were 120 mm long, 120 mm wide and 2 mm thick. A sheet (test piece) was prepared. This sheet was used for various evaluations. The results are also shown in Table 2.
(1) Melt flow rate (MFR)
According to JIS K7210, it measured as 190 degreeC and the load 21N.
(2) Cyclohexane insoluble matter Measured at 23 ° C by the method described in the text.
(3) Hardness (Duro E)
Based on JIS K6253, the hardness 5 seconds after the start of measurement was measured and used as an index of flexibility.
(4) Hardness (Duro A)
In accordance with JIS K6253, the hardness at 5 seconds after the start of measurement in duro A hardness was measured and used as an index of flexibility.
(5) Tensile breaking strength and tensile breaking elongation Measured according to JIS K6251.
(6) Compression set Measured under conditions of 70 ° C. and 22 hours in accordance with JIS K6262, and used as an index of rubber elasticity.
(7) Rebound resilience According to JIS K6255, it was measured at 23 ° C. using a Lüpke rebound resilience tester and used as an index of rubber elasticity.
(8) Molding appearance (bleed test of mineral oil softener)
From the sheet, a rectangular test piece having a length of 40 mm and a width of 30 mm was punched out, and the test piece was allowed to stand in a thermostatic bath at 5 ° C. for 168 hours.
○: No bleeding of mineral oil softener ×: With bleeding of mineral oil softener

[Examples 2-3 and Comparative Examples 1-2]
Except having used each raw material component by the mixture ratio of Table 2, it obtained each thermoplastic elastomer composition like Example 1, and evaluated it. The results are also shown in Table 2.
For Comparative Example 2, the oil-extended rubber (II) shown in Table 1 was prepared in the same manner as in Example 1, and the oil-extended rubber (II) and other raw material components were used. Each raw material composition was obtained by mixing at a blending ratio of 2.

Comparative Example 3
Oil-extended rubber (I) and other raw material components were mixed at a blending ratio shown in Table 2 to obtain a raw material composition. This raw material composition was put into a pressure type kneader (capacity 10 liters, manufactured by Moriyama Co., Ltd.) preheated to 150 ° C., and 40 rpm (shear rate 200 / sec) until the polyolefin resin melted and each component was uniformly dispersed. ) For 15 minutes, and then the obtained kneaded material in a molten state was pelletized by a feeder ruder (manufactured by Moriyama Co., Ltd.) to obtain a thermoplastic elastomer composition and evaluated. The results are also shown in Table 2.

From the results shown in Table 2, Comparative Example 1 was an example not containing a hydrogenated diene polymer, and the mineral oil softener bleeded out from the surface of the molded product, and the appearance was poor. Comparative Example 2 includes a hydrogenated diene polymer, but since the intrinsic viscosity of the ethylene / α-olefin copolymer is less than 3.5 dl / g, the mineral oil softener bleeds out and the appearance is It was bad. Further, Comparative Example 3 is an example in which dynamic crosslinking is not performed, the mechanical strength is insufficient due to inferior tensile properties, the compression set is high, the mineral oil softener bleeds out, and the appearance is It was bad.
On the other hand, it can be seen that the thermoplastic elastomer compositions of Examples 1 to 3 are very low in hardness (duro E) of 54 to 55 and hardness (duro A) of 22 to 26 and excellent in flexibility. Furthermore, the compression set is very small as 29 to 33%, the rebound resilience is sufficiently high as 57 to 68%, and the rubber elasticity is excellent. In addition, no bleed-out phenomenon was observed, and the appearance was good.

[Examples 4-5, Comparative Examples 4-5]
1. Preparation of thermoplastic elastomer composition Table 3 shows the oil-extended rubber (X), polyolefin-based resin, mineral oil-based softener, hydrogenated diene-based polymer, and additives (excluding the crosslinking agent and crosslinking aid) shown below. The mixture was mixed in the same proportion as in Example 1 and pelletized.
Next, the pellets, the crosslinking agent and the crosslinking aid were added to a Henschel mixer at the ratio shown in Table 3, mixed for 30 seconds, and then subjected to dynamic heat treatment using a twin-screw extruder as in Example 1. Extrusion was performed to obtain three types (A, B, C) of pellet-shaped thermoplastic elastomer compositions.

(1) Oil-extended rubber (X)
Oil-extended copolymer rubber 1: Ethylene / propylene / 5-ethylidene-2-norbornene terpolymer (ethylene content 66 mol%, 5-ethylidene-2-norbornene content 4.5 mol%, intrinsic viscosity 5.5 dl / g) 50% by mass, paraffinic softener 50% by mass
(2) Polyolefin resin (I) Crystalline polypropylene Product name “Novatech FL25R” (density: 0.90 g / cm ³ , MFR (temperature 230 ° C., load 2.16 kg); 23 g / 10 min) manufactured by Nippon Polychem Co., Ltd. Was used.
(II) Propylene / 1-butene amorphous copolymer, manufactured by Ube Lexen, trade name “UBETAC APAO UT 2780” (propylene monomer unit amount: 71 mol%, melt viscosity: 8,000 cPs, density; 87 g / cm ³ , crystallinity by X-ray diffraction; 0%, number average molecular weight Mn in terms of polystyrene by GPC; 6,500).

(3) Mineral oil-based softener A trade name “Diana Process Oil PW90” (paraffinic mineral oil) manufactured by Idemitsu Kosan Co., Ltd. was used.
(4) Hydrogenated diene polymer (I) Styrene / butadiene / isoprene hydrogenated diene polymer, trade name “Septon 4077” manufactured by Kuraray Co., Ltd. (styrene monomer unit amount: 30 mol%, specific gravity: 0.91 Hydrogenation rate: 98%, toluene solution viscosity (30 ° C., concentration 5 mass%); 300 mPa · s, melt flow rate (230 ° C., 21.2 N) does not flow and cannot be measured).

(5) Additive (i) Cross-linking agent The trade name “Perhexa 25B-40” (5-dimethyl-2,5-di (t-butylperoxy) hexane) manufactured by NOF Corporation was used.
(Ii) Crosslinking aid Divinylbenzene (purity: 96%) manufactured by Nippon Steel Chemical Co., Ltd. was used.
(Iii) Anti-aging agent The brand name “Irganox 1010” (tetrakis [methylene 3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] methane) manufactured by Ciba Specialty Chemicals was used.

2. Evaluation of Thermoplastic Elastomer Composition The three types of thermoplastic elastomer composition pellets obtained above were processed by an injection molding machine (manufactured by Nippon Steel, model “N-100”), and the length was 120 mm, the width was 120 mm, and A sheet (test piece) having a thickness of 2 mm was prepared. This sheet was used for various evaluations. The results are also shown in Table 3.
(1) Oil bleed property The oil bleed property after leaving at 80 degreeC and 72 hours conditions was visually evaluated.
○: No bleeding of mineral oil softener ×: With bleeding of mineral oil softener

3. Production of a container with a seal part Production of a container with a seal part was carried out by a die slide injection molding method (M-DSI method; trademark) using 220EII-P2M (two-color injection molding machine) manufactured by Nippon Steel Works. After the body part side was molded with polystyrene (grade H230 manufactured by Nippon Polystyrene Co., Ltd.) (cylinder temperature 210 ° C., mold temperature 50 ° C.), the seal part side was continuously molded with a thermoplastic elastomer composition (cylinder temperature 210 ° C., The mold temperature was 50 ° C.) to obtain a container with a seal portion. FIG. 1 shows the obtained container 10 with a seal part, and FIG. 2 shows a case in which the seal part 1 made of the low-hardness seal material of the present invention constituting the container 10 with the seal part is separated from the housing part 2. It is a photograph showing the state.

4). Seal performance evaluation method (test method)
As shown in FIG. The container with a sealing material (two-color molded product) 10 produced in the above was filled with 90% of water 15. Next, the container 10 was covered with a lid 11 and the ends were fixed with double clips (manufactured by KOKUYO: Cree 34, mouth width 25 mm) 12 (eight pieces). Reference numeral 14 denotes a packing. The container 10 was dropped from a height of 1 m onto the corrugated paper 13, and water leakage in the container 10 was confirmed. In addition, the test was changed 5 times (n = 5) by changing the dropping direction with one sample. The results are shown in Table 4.

(Evaluation results)
As is apparent from the results shown in Table 4, the low hardness sealing material (thermoplastic elastomer composition = A, B) according to the present invention did not leak and had good sealing properties. On the other hand, a sealing material using a thermoplastic elastomer composition having a hardness exceeding 40 has poor sealing properties.

  Since the thermoplastic elastomer composition of the present invention is excellent in flexibility and rubber elasticity (rebound resilience, compression set), it is used for automobile bumpers, exterior moldings, gaskets for wind seals, gaskets for door seals, and gaskets for trunk seals. , Roof side rails, emblems, inner panels, door trims, console box and other outer and outer skin materials, weather strips, leather seats that require scratch resistance, aircraft and ship sealing materials and inner and outer skin materials, etc. Civil engineering / architecture sealing materials, interior / exterior skin materials or waterproof sheet materials, etc., sealing materials for general machinery / equipment, etc., weak electrical parts / water supply packing, sealing materials in fuel cell stacks, skin materials, housings, etc. Track pad, roll for information equipment, cleaning blade, film for electronic parts, semiconductor Protective films, sealing materials, image protective films such as photographs, decorative films for building materials, medical equipment parts, electric wires, household goods, sports equipment, etc. in the manufacturing process of flat panel displays (FPD) such as LCD devices Can be widely used for processed products.

The low-hardness sealing material of the present invention can be molded by injection molding, extrusion molding, hollow molding, compression molding, vacuum molding, laminate molding, calendar molding, etc., has extremely low hardness, excellent sealing properties, and mineral oil-based Since the softener does not bleed out and is excellent in various properties such as low compression set, it can be suitably used as a sealing material for general machines and devices. In addition, this sealing material is made of a thermoplastic elastomer composition, can be recycled, and is extremely excellent in terms of global environment and resource saving.
And the container which integrally molded this low hardness sealing material and the housing | casing by two-color injection molding can accommodate various contents, eliminates a leak reliably, and can be used in comfort at the time of use and conveyance.

[0002]
A sealing material is provided.
(1) [A] 5 to 60% by mass of an ethylene / α-olefin copolymer having an intrinsic viscosity of 3.5 dl / g or more measured in a decalin solvent at 135 ° C.
[B] 1-20% by mass of a polyolefin-based resin and 30-94% by mass of a [C] mineral oil-based softening agent (provided that the total of [A], [B] and [C] is 100% by mass). For a total of 100 parts by mass
[D] 0.1 to 50 parts by mass of a hydrogenated diene polymer having a toluene solution viscosity (30 ° C., concentration 5% by mass) of 42 mPa · s or more,
At least the [A] ethylene / α-olefin copolymer and the [B] polyolefin resin are dynamically heat-treated in the presence of a crosslinking agent, do not contain a (meth) acrylate resin,
Thermoplastic elastomer composition.
(2) [X] [A1] 20-80% by mass of an ethylene / α-olefin copolymer having an intrinsic viscosity of 3.5 dl / g or more measured in decalin solvent at 135 ° C. and [C1] mineral oil softener 5 to 60% by mass of an oil-extended rubber comprising 20 to 80% by mass (provided that the total of [A1] and [C1] is 100% by mass),
[B1] 1 to 20% by mass of a polyolefin-based resin and 30 to 94% by mass of [C2] mineral oil-based softener (however, the total of [X], [B1] and [C2] is 100% by mass). For a total of 100 parts by mass
[D1] Contains 0.1 to 50 parts by mass of a hydrogenated diene polymer having a toluene solution viscosity (30 ° C., concentration of 5% by mass) of 42 mPa · s or more,
At least the [A1] ethylene / α-olefin copolymer and the [B1] polyolefin resin are dynamically heat-treated in the presence of a crosslinking agent, do not contain a (meth) acrylate resin,
Thermoplastic elastomer composition.
(3) The hydrogenated diene polymer [D] includes a hydrogenated polymer containing a monomer unit composed of a conjugated diene compound, a monomer unit composed of a conjugated diene compound, and a vinyl aromatic compound. The thermoplastic elastomer composition according to the above (1) or (2), which is at least one selected from a hydrogenated polymer containing a monomer unit.
(4) The thermoplastic elastomer composition according to any one of (1) to (3), wherein the durometer E hardness according to JIS K6253 is 80 or less.
(5) The ethylene unit constituting the ethylene / α-olefin copolymer [A] and [A1].

[0002]
A sealing material is provided.
(1) [A] 5 to 60% by mass of an ethylene / α-olefin copolymer having an intrinsic viscosity of 3.5 dl / g or more measured in a decalin solvent at 135 ° C.
[B] Polyolefin-based resin 1 to 20% by mass and [C] Mineral oil-based softener 30 to 94% by mass (provided that the total of [A], [B] and [C] is 10
0% by mass. ) For a total of 100 parts by mass
[D] 0.1 to 50 parts by mass of a hydrogenated diene polymer having a toluene solution viscosity (30 ° C., concentration 5% by mass) of 42 mPa · s or more,
At least the [A] ethylene / α-olefin copolymer and the [B] polyolefin resin are dynamically heat-treated in the presence of a crosslinking agent, do not contain a (meth) acrylate resin, and are JIS Duro A hardness according to K6253 is 42 or less,
Thermoplastic elastomer composition.
(2) [X] [A1] 20-80% by mass of an ethylene / α-olefin copolymer having an intrinsic viscosity of 3.5 dl / g or more measured in decalin solvent at 135 ° C. and [C1] mineral oil softener 2
5 to 60% by mass of oil-extended rubber consisting of 0 to 80% by mass (provided that the total of [A1] and [C1] is 100% by mass),
[B1] 1 to 20% by mass of a polyolefin-based resin and 30 to 94% by mass of [C2] mineral oil-based softener (however, the total of [X], [B1] and [C2] is 100% by mass). For a total of 100 parts by mass
[D1] Contains 0.1 to 50 parts by mass of a hydrogenated diene polymer having a toluene solution viscosity (30 ° C., concentration of 5% by mass) of 42 mPa · s or more,
At least the [A1] ethylene / α-olefin copolymer and the [B1] polyolefin resin are dynamically heat-treated in the presence of a crosslinking agent, do not contain a (meth) acrylate resin, and are JIS Duro A hardness according to K6253 is 42 or less,
Thermoplastic elastomer composition.
(3) The hydrogenated diene polymer [D] includes a hydrogenated polymer containing a monomer unit composed of a conjugated diene compound, a monomer unit composed of a conjugated diene compound, and a vinyl aromatic compound. The thermoplastic elastomer composition according to the above (1) or (2), which is at least one selected from a hydrogenated polymer containing a monomer unit.
(4) The thermoplastic elastomer composition according to any one of (1) to (3), wherein the durometer E hardness according to JIS K6253 is 80 or less.
(5) The ethylene unit constituting the ethylene / α-olefin copolymer [A] and [A1].

Claims (16)

[A] an ethylene / α-olefin copolymer having an intrinsic viscosity of 3.5 dl / g or more measured at 135 ° C. in a decalin solvent, 5 to 60% by mass;
[B] 1-20% by mass of a polyolefin-based resin and 30-94% by mass of a [C] mineral oil-based softening agent (provided that the total of [A], [B] and [C] is 100% by mass). For a total of 100 parts by mass
[D] 0.1 to 50 parts by mass of a hydrogenated diene polymer,
At least the [A] ethylene / α-olefin copolymer and the [B] polyolefin resin are dynamically heat-treated in the presence of a crosslinking agent,
Thermoplastic elastomer composition. [X] [A1] ethylene / α-olefin copolymer having an intrinsic viscosity of 3.5 dl / g or more measured at 135 ° C. in a decalin solvent and [C1] mineral oil softener 20-80 5-60 mass% of oil-extended rubber consisting of mass% (however, the sum of [A1] and [C1] is 100 mass%),
[B1] 1 to 20% by mass of a polyolefin-based resin and 30 to 94% by mass of [C2] mineral oil-based softener (however, the total of [X], [B1] and [C2] is 100% by mass). For a total of 100 parts by mass
[D1] containing 0.1 to 50 parts by mass of a hydrogenated diene polymer,
At least the [A1] ethylene / α-olefin copolymer and the [B1] polyolefin resin are dynamically heat-treated in the presence of a crosslinking agent,
Thermoplastic elastomer composition. The hydrogenated diene polymer [D] is a hydrogenated polymer containing a monomer unit composed of a conjugated diene compound, and a single unit composed of a monomer unit composed of a conjugated diene compound and a vinyl aromatic compound. The thermoplastic elastomer composition according to claim 1 or 2, wherein the thermoplastic elastomer composition is at least one selected from hydrogenated products of polymers containing body units. The thermoplastic elastomer composition according to any one of claims 1 to 3, wherein the durometer E hardness according to JIS K6253 is 80 or less. The content of the ethylene monomer units constituting the ethylene / α-olefin copolymers [A] and [A1] is all the units including the monomer units composed of an ethylene monomer unit and an α-olefin compound. The thermoplastic elastomer composition according to any one of claims 1 to 4, which is 35 to 95 mol% when the total of the monomer units is 100 mol%. The thermoplastic elastomer composition according to any one of claims 1 to 5, wherein the mineral oil softeners [C], [C1] and [C2] are paraffinic mineral oils. The cross-linking agent includes 1,3-bis (t-butylperoxyisopropyl) benzene, 2,5-dimethyl-2,5-di (t-butylperoxy) hexyne-3, 2,5-dimethyl-2, An organic peroxide selected from 5-di (t-butylperoxy) hexane, α, α-bis (t-butylperoxy) diisopropylbenzene, dicumyl peroxide and di-t-butyl peroxide. The thermoplastic elastomer composition according to any one of 1 to 6. The thermoplastic elastomer composition according to any one of claims 1 to 7, wherein a cyclohexane insoluble content at 23 ° C of the ethylene / α-olefin copolymer in the thermoplastic elastomer composition is 60% by mass or more. A molded article comprising the thermoplastic elastomer composition according to any one of claims 1 to 8. A low-hardness sealing material comprising the thermoplastic elastomer composition according to claim 1. The low-hardness sealing material according to claim 10, which has a duro A hardness of 40 or less in accordance with JISK6253. The low hardness sealing material according to claim 10 or 11, which is formed in any one shape selected from an O-ring shape, a sheet shape, and a rod shape. The container which uses the low-hardness sealing material in any one of Claims 10 thru | or 12 as a component. A container formed by injection molding of a composite composed of a seal portion made of the low hardness seal material according to any one of claims 10 to 12 and a housing portion. The container according to claim 14, wherein the casing is made of a thermoplastic resin and / or a thermoplastic elastomer composition and is recyclable. A toner case comprising the low-hardness sealing material according to claim 10 as a component.

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